(i) Technical Field
The present invention relates to an image processing apparatus, an image processing method, and a computer readable medium and computer data signal for processing image.
(ii) Related Art
In the related art, it is a practice to implement a color-limiting process to reduce the number of colors in use on an image. The color-limiting process allows for reducing the various noises and irregularities contained in the image, e.g. printing irregularities on the original and scanning noises caused in reading out where the image is a read one out of the original by means of an image reader, and hand-written irregularities where hand-written ones are included. Meanwhile, in compressing the image, the process can reduce compression noises while improving the ratio of compression.
The color-limiting process is to be realized by selecting some number of representative colors out of the colors used in the image and then replacing the colors of the image into the representative colors.